Refrigerated transport units can include mobile containers, such as a trailer unit, a container, or a railway car that may have a transport refrigeration system to control a temperature of an internal space of the containers. Refrigerated transport units can be used to transport perishable products, and the temperature of the refrigerated transport units may be controlled to limit loss of the cargo during transportation. The temperature of the refrigerated transport units may be controlled by a TRU.
Some TRUs can include a generator set (genset) that supplies power to a compressor or other electronic components of the transport refrigeration system. These gensets are typically attached directly to the container or container chassis, and include a prime mover (such as an engine) to power the generator. The prime mover is typically a fuel-powered engine such as a diesel engine, a gasoline engine or a natural gas engine. In some other configurations, the prime mover can be mechanically coupled to the compressor of the TRU to drive the compressor of the TRU, for example, by a belt drive. In these configurations, the genset is generally not required.
The fuel combustion in combustion chambers of the engine can generate power to drive the engine. However, the combustion of fuel in the fuel-powered engine can emit environmentally harmful exhaust and particles such as oxides of nitrogen (NOx), carbon monoxide (CO), hydrocarbon (HC), carbon dioxide (CO2) and particulate matter (PM), and can also produce noise.
The composition of the engine exhaust often may have to comply with emission regulations. For example, the exhaust of the TRU engine may have to meet or exceed the requirement set forth by the United States Environmental Protection Agency, as well as requirements set forth by other governments such as in Japan, Europe countries, etc. In some places, the noise level of the engine may also be regulated. For example, in a residential area, zoning regulations may restrict the noise level of the engine. In addition, in some situations, for example during a resting period taken by the TRU vehicle operator, noise reduction may also be desired.
Devices have been developed to reduce the environmental harmful exhaust and noise of the engine. For a diesel engine, such devices may include for example turbocharger, an exhaust gas recirculation (EGR), an EGR cooler, a diesel particulate filter (DPF), a diesel oxidation catalyst (DOC), and a common rail (CR) fuel injection system. The turbocharger can help reduce PM, NOx, HC, CO, and CO2. The EGR and/or EGR cooler can help reduce NOx. The DOC can help reduce unburned HC. The DPF can help reduce PM. A diesel engine equipped with these devices may be able to comply with the emission regulations; however these devices may also increase the initial equipment cost and associated reoccurring maintenance costs for the diesel engine.
The CR system generally includes a high pressure fuel pump. The high pressure fuel pump can pressurize the fuel and pump the pressurized fuel to a high pressure fuel rail (the common rail) that feeds all of the individual fuel injectors. An engine control unit (ECU) can control the individual fuel injector so as to control fuel injection parameters, such as quantity, timing and duration of the fuel injection by each fuel injector into the corresponding combustion chamber. The ECU can also be configured to control an air inlet and the turbocharger so as to control an amount of air supplied to the combustion chambers of the engine. By controlling the amount of air supply and fuel injection characteristics, the ECU can control the engine performance.